Conventionally, the following procedure is followed when a magnetic resonance imaging apparatus (hereinafter, “MRI apparatus”) performs imaging. First, a subject is positioned in the MRI apparatus in such a manner that an imaging target area is placed at the center of the magnetic field in which a magnetostatic field and a gradient magnetic field are superposed on each other. Next, a positioning image is taken in the MRI apparatus, and is displayed on the display unit of the MRI apparatus. Then, an operator such as a technician designates a region of interest (ROI) by use of the displayed positioning image. Thereafter, main imaging (hereinafter, “main scanning”) is executed in the MRI apparatus, and a medical image is reconstructed in the MRI apparatus in accordance with the designated ROI.
Imaging on the MRI apparatus may adopt a multi-coil system (e.g., Japanese Patent Application Laid-open No. 10-179551, U.S. Pat. No. 6,794,872, and Japanese Patent Application Laid-open No. 2008-29834). The multi-coil system is a reception coil that includes multiple element coils to receive magnetic resonance signals radiated from the subject (hereinafter, “nuclear magnetic resonance (NMR) signals”). When the multi-coil system is used, NMR signals are collected in accordance with channels that are assigned to the element coils. For this reason, a technology with which an element coil for imaging is automatically selected to collect NMR signals on a channel the most suitable for imaging has been offered. For example, the MRI apparatus identifies an element coil overlapping the center of the magnetic field, and selects the identified element coil as an element coil for imaging.
It has been difficult, however, for an operator such as a technician to judge whether a channel is suitably selected in accordance with the above technology. For example, because the subject is not suitably positioned, the imaging target area may be shifted from the center of the magnetic field, or the selection of the element coil that overlaps the center of magnetic field may not always mean the selection of the most suitable channel for imaging. It is yet difficult to judge which channel should be selected based on the positioning image. For this reason, if the channel selection is in doubt, the operator has to, for example, retake a positioning image. Moreover, if main scanning is executed without noticing that an unsuitable channel is selected, the operator has to redo, for example, the main scanning.